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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/feature/goddard/2017/nasa-mission-uncovers-dance-of-electrons-in-space

    You can’t see them, but swarms of electrons are buzzing through the magnetic environment — the magnetosphere — around Earth.
    The electrons spiral and dive around the planet in a complex dance dictated by the magnetic and electric fields. When they
    penetrate into the magnetosphere close enough to Earth, the high-energy electrons can damage satellites in orbit and trigger
    auroras. Scientists with NASA’s Magnetospheric Multiscale, or MMS, mission study the electrons’ dynamics to better understand
    their behavior. A new study, published in Journal of Geophysical Research revealed a bizarre new type of motion exhibited
    by these electrons.

    Exploring Reconnection - Guide Field Off
    https://www.youtube.com/watch?v=YIBG5ZAPwW4
    VIRGO
    VIRGO --- ---
    National Optical Astronomy Observatory Press Release: Punching Above Its Weight, a Brown Dwarf Launches a Parsec-Scale Jet
    https://www.noao.edu/news/2017/pr1701.php

    Astronomers using the SOAR telescope at the Cerro Tololo Inter-American Observatory report the discovery of a spectacular extended jet
    from a young brown dwarf. With masses too low to sustain hydrogen fusion in their interiors, brown dwarfs occupy the mass range between
    stars and giant planets. While young stars are commonly found to launch jets that extend over a light year or more, this is the first
    jet with a similar extent detected from a brown dwarf. The result lends new insight into how substellar objects form.

    Intrinsically faint, brown dwarfs have been more elusive and difficult to study than stars. Although they are often portrayed as exotic
    creatures as a result, brown dwarfs are actually far more numerous in our Galaxy than stars like the Sun. The discovery, accepted for
    publication in the Astrophysical Journal, supports the emerging picture that brown dwarfs form similarly to stars.

    The image shows the jet, HH 1165, launched by the brown dwarf Mayrit 1701117 in the outer periphery of the 3 million year old sigma Ori
    cluster. Traced by emission from singly ionized sulfur, which appears green in the image, the jet extends 0.7 light years (equivalent to
    0.2 parsecs) northwest of the brown dwarf. The emission knots along the jet reveal that the mass loss is time variable, probably a result
    of episodic accretion onto the brown dwarf. The red nebulosity southeast of the brown dwarf is a reflection nebula that traces the outflow
    cavity in the direction of the counterjet.

    VIRGO
    VIRGO --- ---
    Snowball Earth melting led to freshwater ocean 2 kilometres deep | New Scientist
    https://www.newscientist.com/...25-snowball-earth-melting-led-to-freshwater-ocean-2-kilometres-deep/

    A little more than 600 million years ago, you could have drunk from the ocean.

    After an extreme ice age known as snowball Earth, in which glaciers extended to the tropics and ice up to a kilometre thick covered the oceans,
    the melt formed a thick freshwater layer that floated on the super-salty oceans.

    Those freshwater surface seas lasted far longer than thought, according to research by Dorian Abbot, a geologist at the University of Chicago,
    and his colleagues. Their mathematical models showed that it took around 50,000 years for the two layers to fully merge.

    “This is interesting because the modern ocean mixes on a timescale of only about 1000 years,” says Abbot.

    The much slower mixing was due to the huge density and temperature differences between the layers. During the snowball phase, half the oceans’
    water ended up as snow and ice. The remaining seas were twice as salty as today, and near their freezing point.

    Once the ice melted, driven by a runaway greenhouse effect caused by volcanic eruptions, it formed a freshwater layer up to 2 kilometres thick.
    VIRGO
    VIRGO --- ---
    Our View of the Cosmos Is About to Get a Tremendous Upgrade
    https://futurism.com/2-the-way-were-looking-for-alien-life-is-changing/

    Nasa's Kepler Telescope has confirmed 3486 exoplanets, 361 of which it considers terrestrial:
    how are scientists responding to the question of how to detect life on these promising but distant worlds?

    Transiting Exoplanet Survey Satellite (TESS)
    https://www.youtube.com/watch?v=mpViVEO-ymc
    VIRGO
    VIRGO --- ---
    Podpořte "Planetární stezka údolím Vltavy" na Startovači - Projekty | Startovač
    https://www.startovac.cz/projekty/planetarni-stezka-udolim-vltavy/
    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/...re/goddard/2017/nasas-van-allen-probes-spot-man-made-barrier-shrouding-earth

    Humans have long been shaping Earth’s landscape, but now scientists know we can shape our near-space environment as well.
    A certain type of communications — very low frequency, or VLF, radio communications — have been found to interact with particles
    in space, affecting how and where they move. At times, these interactions can create a barrier around Earth against natural high
    energy particle radiation in space. These results, part of a comprehensive paper on human-induced space weather, were recently
    published in Space Science Reviews.

    NASA's Van Allen Probes Find Human-Made Bubble Shrouding Earth
    https://www.youtube.com/watch?v=cFYoYUBGw4s
    VIRGO
    VIRGO --- ---
    Vzpomínáte loni na tu přeukrutnou pátračku? :)

    Nálezce přiznal meteorit od Hradce skoro po roce, teď ho má s rodokmenem - iDNES.cz
    http://hradec.idnes.cz/...-hradec-kralove-dsr-/hradec-zpravy.aspx?c=A170517_104247_hradec-zpravy_tuu

    VIRGO
    VIRGO --- ---
    Astronaut Mike Massimino: Scariest moment of my life... Today in 2009, NASA
    instructed me to rip the handrail off +Hubble Space Telescope, to save STIS.

    Astronauts Use Brute Force to Rip Handrail Off Hubble
    http://www.space.com/6711-astronauts-brute-force-rip-handrail-hubble.html

    VIRGO
    VIRGO --- ---
    Astronomers Found Spirals Inside a Dust Gap of a Young Star Forming Disk
    http://www.almaobservatory.org/...omers-found-spirals-inside-a-dust-gap-of-a-young-star-forming-disk

    Planets form within disks composed of dust grains and gas. Planets can gather dust grains from their orbits, resulting in dust gaps or cavities,
    and can also cause spiral waves within the parental disks based on theoretical predictions. To understand where and when planets can form at early
    stages, ALMA’s capability of seeing disk material with high resolution can depict smoking-gun evidence of infant planets hidden in disks.

    Both dust gaps and spirals have been seen separately in a handful of disks. The new ALMA images of AB Aurigae clearly depict gas spirals inside
    a wide dust gap. These first reported gas spirals within a dust gap might indicate that there are at least 2 planets within this system. One planet
    at a distance of 80 astronomical units (au; the distance between the Sun and Earth) from the star is required to create the sharp dust ring.
    An additional planet at 30 au or closer from the star is required to produce such spirals.

    VIRGO
    VIRGO --- ---
    Anna Bilous & Vlad Kondratiev: LOFAR's view on pulsar sky
    ASTRON JIVE Daily Image
    http://www.astron.nl/dailyimage/index.html?main.php?date=20160909

    Imagine you are a sentient alien creature with a pair of superb radio eyes, capable of discerning
    even the most minute splashes of radio emission... how would the night sky look to you? The image
    above may give a clue to that. On top of the diffuse black-and-white Galactic background, the swarm
    of color dots provides a one-second glimpse into the life of 158 northern pulsars, with the course
    of time slowed down by a factor of 10.

    These pulsars were observed within the LOFAR Pulsar HBA Census -- a large project which aims at
    creating the first uniform low-frequency (110-188 MHz) portrait of all known non-recycled pulsars
    in certain regions of the sky. All 196 pulsars with well-known positions within the grey lines were
    observed, regardless of their estimated brightness and scattering level. Only 38 of those pulsars
    escaped detection (still dots with black edges).

    VIRGO
    VIRGO --- ---
    JWST getting ready for it's end-to-end system testing at NASA Johnson Center. Via Alberto Conti‏.



    VIRGO
    VIRGO --- ---
    FADO—a ground-breaking tool to reconstruct the history of galaxies
    https://phys.org/news/2017-05-fadoa-ground-breaking-tool-reconstruct-history.html

    FADO is a new analysis tool developed by Instituto de Astrofísica e Ciências do Espaço (IA) astronomers Jean Michel Gomes and
    Polychronis Papaderos, which uses light emitted by both stars and ionized gas in a galaxy to reconstruct its formation history by
    means of genetic algorithms. This tool was presented in a recent article, accepted for publication in the journal Astronomy & Astrophysics.

    VIRGO
    VIRGO --- ---
    Cassini: The Grand Finale: Hall of Fame
    https://saturn.jpl.nasa.gov/galleries/hall-of-fame/

    VIRGO
    VIRGO --- ---
    http://www.spaceflightinsider.com/...unting-camera-successfully-tested-international-space-station/

    A highly advanced and specialized university-built camera has been successfully tested at the International Space Station (ISS).
    The instrument, known as the Charge Injection Device (CID), is designed to capture light from distant faint objects such as extrasolar worlds.

    CID cameras, originally developed by General Electric Co. in 1972, measure light from individual pixels without affecting the surrounding pixels.
    This enables the capture of pictures with extremely bright as well as extremely faint objects. CID is able to capture images of very bright and
    very dim objects in a single scene. Therefore, it could be useful in acquiring images of exoplanets orbiting bright host stars. Moreover, it
    could become a relatively simple and inexpensive tool for identifying potential Earth-like planets beyond our solar system.

    VIRGO
    VIRGO --- ---
    Astronomers characterize two 'super-Earths' in a distant planetary system
    https://phys.org/news/2017-05-astronomers-characterize-super-earths-distant-planetary.html

    An international team of astronomers led by Eike W. Guenther of the Thuringian State Observatory in Tautenburg, Germany,
    has characterized two "super-Earth" exoplanets orbiting a distant star designated K2-106, determining their size, mass
    and density. The new findings were presented in a paper published May 11 on the arXiv pre-print server.

    Located approximately 825 light years away from the Earth, K2-106 is a 5 billion-year-old star of spectral type G5. With
    a radius of about 0.83 solar radii, the star is 7 percent less massive than the sun. In 2016, researchers detected two
    planets transiting this star with orbital periods of 0.57 and 13.3 days.

    VIRGO
    VIRGO --- ---
    Featured news - Scientists take first tentative steps to explore potential climate of Proxima B - University of Exeter
    http://www.exeter.ac.uk/news/featurednews/title_583299_en.html

    Scientists take first tentative steps to explore potential climate of Proxima B

    The quest to discover whether a planet orbiting our closest neighbouring star, Proxima Centauri (4.2 light
    years or 25 trillion miles from Earth), has the potential to support life has taken a new, exhilarating twist.
    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/feature/jpl/movie-shows-ceres-at-opposition-from-sun

    NASA's Dawn spacecraft successfully observed Ceres at opposition on April 29, taking images from a position exactly between the sun and Ceres’ surface.
    Mission specialists had carefully maneuvered Dawn into a special orbit so that the spacecraft could view Occator Crater, which contains the brightest
    area of Ceres, from this new perspective.

    A new movie shows these opposition images, with contrast enhanced to highlight brightness differences. The bright spots of Occator stand out particularly
    well on an otherwise relatively bland surface. Dawn took these images from an altitude of about 12,000 miles (20,000 kilometers).

    VIRGO
    VIRGO --- ---
    Variable Winds on Hot Giant Exoplanet Help Study of Magnetic Field | Planetary Science Institute
    http://www.psi.edu/news/press-releases/

    Senior Scientist Tamara M. Rogers of the Planetary Science Institute has discovered that substantial variability in the winds on the hot giant
    exoplanet HAT-P-7b are due to magnetism, and used those measurements to develop a new method to constrain the magnetic field of such an object.

    HAT-P-7b was discovered by NASA’s Kepler Mission in 2008. It is nearly 40 percent larger and nearly 80 percent more massive than Jupiter.
    It orbits its star every couple of days, and is so close that dayside temperature may be 2,200 degrees Kelvin (3,500 degrees Fahrenheit)
    with a night side 1,000 Kelvin (1,340 degrees Fahrenheit) cooler.

    VIRGO
    VIRGO --- ---
    Obscured Supermassive Black Holes in Galaxiessu201717 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201717

    CfA astronomers Francesca Civano and Stefano Marchesi and their colleagues prepared a precisely defined sample of obscured AGN -- those whose infrared emission
    is more than twenty times larger than its X-ray emission (the X-ray emission was measured by the Chandra X-ray Observatory). They first collected a set of 265
    AGN and then determined which ones were "obscured" by calculating the infrared emission of each to ratio with its X-ray emission. They did this by assembling
    the full spectral distribution of the radiation, combining infrared with UV and optical data and then modeling the entire distribution to determine the total
    infrared component from the AGN alone with a code that models and subtracts the contributions from stars and other processes. Once they had the infrared value,
    they could tell which ones qualified as "obscured." Their final sample of obscured AGN had 182 objects.

    VIRGO
    VIRGO --- ---
    New 'styrofoam' planet provides tools in search for habitable planets
    https://phys.org/news/2017-05-styrofoam-planet-tools-habitable-planets.html

    Fifth-graders making styrofoam solar system models may have the right idea. Researchers at Lehigh University have discovered a new planet orbiting
    a star 320 light years from Earth that has the density of styrofoam. This "puffy planet" outside our solar system may hold opportunities for testing
    atmospheres that will be useful when assessing future planets for signs of life.

    The research, "KELT-11b: A Highly Inflated Sub-Saturn Exoplanet Transiting the V+8 Subgiant HD 93396," is published online in The Astronomical Journal.

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